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					        LIGHTNING PROTECTION




             WAR OF THE LIGHTNING RODS
By Abdul M. Mousa, Ph.D., P.Eng., Fellow IEEE


S
       ince the dawn of civilization, light-
       ning has inflicted a great deal of
       damage on the structures built by
mankind. About 250 years ago, an effec-
tive method of protection became avail-
able when Benjamin Franklin invented
the lightning rod. Its application to power
lines took the form of shield wires. A
great deal of the research done since then
was regarding how to best place the
lightning rods and shield wires so as to
provide effective protection at a reason-
able cost.
     In recent years, the marketplace has
been flooded with products for alterna-
tive protection methods. These include
gadgets that claims to eliminate lightning
[also called Charge Transfer Systems
(CTS)], and rods that claim to emit giant      attempt to define the protected zones of       zations. This escalated to actual court
early streamers that vastly extend their       shield wires and masts/lightning rods.         action against NFPA (National Fire
protective range (ESE devices). This arti-     The great R.H. Golde theorized that such       Protection Association) and others, and
cle explains the requirements for effec-       scale models produce invalid results.          some scientists were humiliated by being
tive lightning protection, and presents the    Field observations on the double circuit       forced to submit to interrogations.
position of the scientific community           345 kV lines of the early 1950s proved              The proponents of CTS and ESE
regarding the claims behind the above          Golde’s theory. The ensuing research led       devices claim to be seeking to introduce
devices.                                       to the development of the electrogeom-         superior lightning protection systems
                                               teric model (EGM). The Rolling Sphere          that better serve the customer. On the
      THE CONVENTIONAL LIGHTNING               Method (RSM), which is widely used in          other hand, their real objective appears to
               PROTECTION SYSTEM               standards, is a method of visualizing the      be to make more profits from the sale of
     The science of lightning protection       application of the EGM, and it was             such systems. One tactic is to get the cus-
was born when Franklin discovered that         developed by R.H. Lee. The RSM                 tomer to pay more on the grounds that
lightning was a form of electricity. The       involves an approximation as it assumes        the offered air terminals can eliminate
conventional protection method consists        the “striking distances” to all objects (air   lightning. As an example of the price
of the following:                              terminals, the ground, and the protected       hike associated with such a claim, the
a) Deploying “air terminals” at suitable       structure) to be equal to one another. The     cost of the CTS device called “Spline
     points above the structure to act as      conventional      lightning      protection    Ball” (US $105) is more than 10 times
     sacrificial termination points for the    method adopted in national and interna-        the cost of a Franklin rod ($6-$10
     lightning strokes.                        tional standards rests on using Franklin       depending on length). It should be noted
b) Dissipating the collected lightning 2       rods that are placed using the RSM.            here that the Spline Ball acts as a one-to-
     charges safely into the ground via                                                       one replacement for the Franklin rod.
     ground rods that are connected to the                     THE DRIVER BEHIND THE          Hence, the customer in effect pays much
     air terminals via “down conductors”.                  ALTERNATIVE AIR TERMINALS          more for a degree of protection which, at
c) Bonding the down conductors to any               In recent years, some vendors of          best, is similar to that of a conventional
     nearby conducting objects in the          alternative air terminals have been wag-       system.
     building to prevent side flashes.         ing a war based on claims that have been            Another tactic is to offer the alterna-
d) Installing suitable surge protection        rejected by the scientific community at        tive system at a cost which is comparable
     devices on the electric and electron-     large. In the process, they lowered the        to that of a conventional system, but pro-
     ic systems of the building.               debate to the point of denying the exis-       vide only one or a few air terminals.
     In the beginning, it was thought that     tence of the extensive research behind         Also, the number of down wires is
the protected zone was described by a          the EGM/RSM. They then attempted to            reduced to one or two. In contrast, a con-
cone around the lightning rod. In the          force their point of view by using threats     ventional system for the same building
early 1940s, C.F. Wagner applied light-        of legal action against the participants in    may require 20 Franklin rods and many
ning impulses to a scale model in an           the debate, both individuals and organi-                          Continued on page 46

Electricity Today Issue 2, 2004                                                                                                       45
      LIGHTNING PROTECTION
Continued from page 45
down wires. This is the practice of the
vendors of ESE devices, and it rests on
the claim of having a protective range
that is much larger than that of the
Franklin rod. On the other hand, the pro-
tective range of an ESE device is practi-
cally equal to that of a Franklin rod. The
result is that the customer pays “the full
price” for a fraction of the protection.
This could have serious consequences to
life and property, especially if the build-
ing houses hazardous materials.
     As implied by the above, the price of
an ESE device is also much higher than        Since the dawn of civilization, lightning has inflicted a great deal of damage on the struc-
that of a Franklin rod. For example, one      tures built by mankind.
manufacturer which offers both systems
charges US $1250 for the ESE device and       downward leader.                               of a CTS.
$10 for a Franklin rod.                             Another important finding of the                             ESE LIGHTNING RODS
                                              Russian scientists is that lightning strokes        ESE devices were invented when
     LIGHTNING ELIMINATION DEVICES            will continue to strike the CTS or the pro-    their predecessors — radioactive rods —
     While the concept itself is much         tected object. However, they suggest that      were banned on the grounds that their
older, the commercialization of CTS           if the stroke arrives beyond a certain dis-    claimed benefit did not justify the result-
started in the early 1970s. Shortly there-    tance from the structure, designated “D”       ing nuclear pollution. An ESE device
after, studies were commissioned by sev-      in Fig. 1, then the opposing field of the      releases a charge at its tip earlier than
eral departments of the US government         cloud of space charge may be able to can-      done by a Franklin rod. The charge is
to evaluate their effectiveness, and the      cel it out, thus inhibiting the formation of   claimed to form a giant upward streamer
results were presented in a report edited     an upward counter leader. Hence the            which acts as an extension to the rod. The
by J. Hughes [1]. The conclusion was that     stroke would terminate elsewhere. Let          downward leader would then connect to
lightning cannot be eliminated and that       “X” be the effective collection radius of      the tip of the streamer, thus vastly extend-
the subject gadgets did not work. This        the structure in the absence of the CTS.       ing the protective range of the rod. If
was confirmed by several subsequent           The “failure ratio” of the CTS would then      such giant streamers existed, it would be
studies. Recently, a comprehensive            be:                                            possible to photograph them with a streak
review of CTS was conducted by                      F = (D/X)2 ...(1)                        camera or a Boys’ camera. The vendors
Professors Uman and Rakov [2]. Again,               Based on the assumption that X =         failed to produce such photographs, yet
the conclusion was that the lightning         3H, “H” being the height of the structure,     continued to insist that their theory was
elimination claim was unfounded. The          and that the downward leader will have a       valid.
above work is of special significance as it   constant charge density of 0.001 C/m, the           Some of the reasons for rejecting the
was widely endorsed by the scientific         Russian scientists suggest that the failure    ESE theory are as follows: a) a streamer
community, including ICLP (Inter-             ratio will be small.                           cannot form before its natural time
national Conference on Lightning                    Contrary to the above, Ref. [3]          because the electric field within the gap
Protection), the American Geophysical         shows that the failure ratio will be almost    will be too low to permit propagation.; b)
Union and the American Meteorological         100% even if the idealized condition           even if the streamer started developing,
Society.                                      upon which the Russian model is based          its speed would be a small fraction of that
     Equally important, Russian scientists    materializes. For one thing, distance X is     assumed in the ESE theory;. c) according
hired by the CTS people themselves            actually much smaller than 3H. Second,         to the EGM, a huge increase in the effec-
agreed with the scientific community          proper modeling of the charge distribu-        tive length of a lightning rod does not
regarding the invalidity of many of the       tion in the downward leader may make           significantly decrease the required num-
claims that the CTS industry aggressive-      distance “D” larger than “X”.                  ber of air terminals.
ly pushed in the past. For example, the             Regardless of the value of the failure        It should be noted that the review by
main claim of the CTS folks has been that     ratio, the admission of the Russian scien-     Uman and Rakov covered both CTS and
their gadgets produce copious amounts of      tists that at least some strokes, especially   ESE devices, and rejected both. The
charge that will neutralize the cloud or at   the ones having larger amplitudes, will        rejection of the ESE theory by indepen-
least form a cloud of space charge that       terminate on the structure renders the         dent scientists is also worldwide.
will neutralize the downward leader. On       CTS not feasible on economic grounds.          Actually, the rejection of ESE theory
the other hand, the Russian scientists        Further measures will still be necessary       goes back to February 1999. At that time,
found the emitted charge to be not much       to enable the structure to cope with direct    ICLP issued an opposing statement that
larger than that produced by a single elec-   lightning strokes. Those same measures         was endorsed by 17 scientists from 15
trode. Further, they found the subject        will also enable it to cope with the rest of   countries [4]. Further, ESE technology
charge to be incapable of neither dis-        the strokes. Hence, there is no justifica-     was rejected by independent scientists in
charging the cloud nor neutralizing the       tion for incurring the additional high cost    France, the birthplace of the ESE theory

46                                                                                                 Electricity Today Issue 2, 2004
                                               can be obtained, free of charge, from the           [5] Gruet, P. (October 2001). A Study
                                               archives of the Lightning Protection                    on Early Streamer Emission
                                               group. To join, just send a blank e-mail                Lightning Rods, INERIS (National
                                               message to: LightningProtection-sub-                    Institute of Environment, Industry
                                               scribe@yahoogroups.com                                  and Hazards), France, 64 pp.
                                                                                                       English highlights of the Report are
                                                                              REFERENCES               given in message #1136 in the
                                               [1] Hughes, J. (Editor). (1977). Review                 archives     of     www.Lightning
                                                   of Lightning Protection Technology                  Protection@yahoogroups.com.
                                                   for Tall Structures, Office of Naval            [6] American Meteorological Society.
                                                   research, Arlington, Virginia,                      (November 2002). “Lightning
                                                   Report No. AD-A075 449, 275 pp. 6                   Protection Systems”, policy state-
                                               [2] Uman, M.A. and Rakov, V.A.                          ment, www.ametsoc.org/AMS/poli-
                                                   (2002). “A Critical Review of                       cy/lightningprot_statement.HTML-
                                                   Nonconventional Approaches to                       29k.
                                                   Lightning Protection”, Bulletin of              [7] Tobias, J. et al. (June 2001). The
                                                   the American Meteorological                         Basis of Conventional Lightning
Fig. 1. Effect of CTS on downward lightning        Society, Vol. 83, No. 12, pp. 1809-                 Protection Technology, Report of
leader.                                            1820.                                               the Federal Interagency Lightning
                                               [3] Mousa, A.M. (July 2003). “Validity                  Protection User Group, DTIC
[5].                                               of the Lightning Elimination                        (Military version of NTIS),
       VALIDITY OF THE CONVENTIONAL                Claim”, Proceedings of the IEEE-                    Catalogue No. ADA396784, Report
       LIGHTNING PROTECTION SYSTEM                 PES Annual Meeting, Toronto,                        No. CECOMTR- 01-5, Source
     The vendors of ESE rods and CTS               Ontario, 6 pp.                                      Code: 412503, 76 pp. Also available
devices often attempt to advance their         [4] Mazzetti, C. and Flisowski, Z. (26                  as section 5.1.9 on the website:
claims by alleging that the basis of the           February 1999). “The ICLP                           www.LightningSafety.com
conventional lightning protection system           Statement’s to the NFPA Draft                       Abdul Mousa is a Specialist
is also questionable. Those allegations            Standard 781”, 2 pp. Included in                Engineer     in   Transmission      and
have been rejected by the scientific com-          section 5.4.3 on the web site of:               Engineering for BC Hydro. ET
munity. Please see the related policy              www.lightningsafety.com
statement       of      the     American
Meteorological Society [6].
     In addition to the above, a report by
Tobias et al [7] proves the effectiveness
                                                                                                       Transformer
of the conventional protection method.                                                             Cooling Products
The Tobias report represents the collec-          A member of the Koch Chemical Technology Group
tive position of 8 respected lightning
experts.                                          Transformer oil cooling products to the Power Generation,
                                                  Transmission & Distribution Industries.
                CONCLUDING REMARKS
      Like the rest of the marketplace,
many false claims exist within the light-
ning protection field. Actually, it is easi-
er to mislead the buyer in this case as
complexity of the subject makes the junk
science arguments of the vendors appear
plausible to him/her. This fact, coupled
with the power of well-financed com-
mercial propaganda campaigns, enabled
the vendors of CTS and ESE devices to
get thousands of people to buy their
products. In some cases, the damage is
limited to overcharging the customer for
non-existent lightning elimination capa-
bilities. In other cases, the customer is
given only a fraction of the required pro-
tection, thus exposing life and property
to risks.
      Potential buyers are advised to pro-
tect themselves by not entertaining any
claim unless the vendor submits proof             Unifin International
that it has been accepted by the scientific       Tel: (519) 451-0310 Toll Free: (888) 451-0310 Fax: (519) 451-1732
community at large.                               www.unifin.com               unifin@kochind.com
      Useful information in this respect

Electricity Today Issue 2, 2004                                                                                                         47